Mounting of a heat exchanger in an air conditioner

ABSTRACT

The combination of a heat exchanger and support structure for the heat exchanger. The heat exchanger includes a first tube sheet having a planar mounting flange which has at least one opening formed therein. The opening defines an edge facing in a predetermined direction. A second tube sheet has a second planar mounting flange which also has at least one opening formed therein, which defines an edge facing in the same predetermined direction. The two tube sheets are spaced from one another with the first and second mounting flanges lying in substantially the same plane. The support structure includes a first planar support surface adapted to receive the flange of the first tube sheet in parallel confronting relationship. The support surface has integrally formed therein an upstanding structural protrusion, which includes a root section and an upper enlarged section, which is configured to pass through the openings in the first flange. The root section and the enlarged section define, together with the planar support surface, a narrow slot configured to receive the edge of the first tube sheets mounting flange therein. A second planar support surface of the support structure is configured the same as the first planar support surface and is adapted to cooperate with the second tube in a like manner. The first tube sheet is provided with a structural portion extending perpendicularly from the first mounting flange. The perpendicular structural portion is spaced from the edge and has an opening formed therein. The upper enlarged section of the structural protrusion of the first support surface is provided with a portion thereof in spaced relation with the perpendicular section of the first tube sheet. The spaced portion has an opening therein in axial alignment with the opening in the perpendicular section. A threaded fastener passes through the opening in the spaced portion and into threaded engagement with the opening in the perpendicular section. As a result, when the first and second tube sheets are positioned with their edges in confronting relation with their mating slots, and the threaded fastener is actuated to engage the perpendicular section, the edges are drawn into engagement with their mating slots to thereby attach the heat exchanger to the first and second support surfaces.

TECHNICAL FIELD

The invention generally relates to air distribution units of the typecommonly used in air conditioning, heating or ventilation systems and,more particularly, to a method of mounting a heat exchange coil in sucha unit.

BACKGROUND ART

In many commercial air conditioning, heating and ventilating systems,treated air is discharged into an area to be conditioned through an airdistribution or conditioning unit. For example, one type of airconditioning system, often referred to as a split system, includesseparate indoor and outdoor units. The outdoor unit includes acompressor, a heat exchanger and a fan. The indoor unit includes a heatexchanger and a fan. In operation, the indoor fan draws air into theindoor unit, through an inlet thereof, and forces the air over theindoor heat exchanger and then out of the indoor unit, through an outletopening therein.

The outdoor fan draws air into the outdoor unit, through an inlet,forces that air over the outdoor heat exchanger and then forces that airout of the outdoor unit through an outlet therein. At the same time, acompressor causes a refrigeration fluid to circulate through and betweenthe indoor/outdoor heat exchangers. At the indoor heat exchanger, therefrigerant absorbs heat from the air passing over that heat exchanger,cooling that air. At the same time, at the outdoor heat exchanger, theair passing over the heat exchanger absorbs heat from the refrigerantpassing therethrough.

In manufacturing the indoor units of such air conditioning systems, themounting of the indoor fans, heat exchanger, and related componentstypically require a number of fasteners of different types. As a result,the labor involved in assembly of such units has been high in view ofthe large number of fasteners required. It is considered extremelydesirable to minimize the number of components required in order tofabricate the indoor units of such an air conditioning system.

DISCLOSURE OF THE INVENTION

The combination of a heat exchanger and support structure for the heatexchanger. The heat exchanger includes a first tube sheet having aplanar mounting flange which has at least one opening formed therein.The opening defines an edge facing in a predetermined direction. Asecond tube sheet has a second planar mounting flange which also has atleast one opening formed therein, which defines an edge facing in thesame predetermined direction. The two tube sheets are spaced from oneanother with the first and second mounting flanges lying insubstantially the same plane. The support structure includes a firstplanar support surface adapted to receive the flange of the first tubesheet in parallel confronting relationship. The support surface hasintegrally formed therein an upstanding structural protrusion, whichincludes a root section and an upper enlarged section, which isconfigured to pass through the openings in the first flange. The rootsection and the enlarged section define, together with the planarsupport surface, a narrow slot configured to receive the edge of thefirst tube sheets mounting flange therein. A second planar supportsurface of the support structure is configured the same as the firstplanar support surface and is adapted to cooperate with the second tubein a like manner. The first tube sheet is provided with a structuralportion extending perpendicularly from the first mounting flange. Theperpendicular structural portion is spaced from the edge and has anopening formed therein. The upper enlarged section of the structuralprotrusion of the first support surface is provided with a portionthereof in spaced relation with the perpendicular section of the firsttube sheet. The spaced portion has an opening therein in axial alignmentwith the opening in the perpendicular section. A threaded fastenerpasses through the opening in the spaced portion and into threadedengagement with the opening in the perpendicular section. As a result,when the first and second tube sheets are positioned with their edges inconfronting relation with their mating slots, and the threaded fasteneris actuated to engage the perpendicular section, the edges are drawninto engagement with their mating slots to thereby attach the heatexchanger to the first and second support surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be better understood and its objects and advantageswill become apparent to those skilled in the art by reference to theaccompanying drawings, in which:

FIG. 1 is a perspective view of the indoor unit of an air conditioner,which embodies the features of the present invention;

FIG. 2 is a right side perspective view of the air conditioner of FIG. 1with the outer cover removed and the heat exchanger shown disassembledfrom the unit;

FIG. 3 is a view similar to FIG. 2 with the heat exchanger installed tothe unit;

FIG. 4 is the detail identified as FIG. 4 in FIG. 3;

FIG. 5 is a simplified illustration of the details of the attachment ofa heat exchanger;

FIG. 6 is a view taken along the line 6—6 of FIG. 4;

FIG. 7 is a simplified left end perspective showing an optionalattachment feature;

FIG. 8 is a front perspective view similar to FIG. 2 with the left-handportion of a heat exchanger broken away; and

FIG. 9 is a perspective exploded view of the air conditioning unit ofFIG. 1.

BEST MODE FOR CARRYING OUT THE INVENTION AND INDUSTRIAL APPLICABILITY

Looking first at FIGS. 1 and 7, the indoor unit 10 of a split system airconditioning system of the type incorporating a heat exchanger mountingaccording to the present invention is illustrated. Briefly, the unit 10includes a main structural support frame 12, which includes a bottompanel 14, a back panel 16 and a top section 18. Attached to the sides ofthe back and top panels are structural internal side covers 20. The sidecovers 20 and the back panel 16 cooperate to support a horizontallyextending fan support panel 22, which includes a pair of rectangularopenings 24 formed therein. Mounted above the fan support panel 22 on apair of inclined surfaces 26, defined by the internal side covers 20 isa heat exchanger coil 25.

Mounted under the top section of the main support frame 12 is an uppercondensate collection pan 28. Mounted in the front of the unit, underthe bottom of the heat exchanger 25, and supported by the front edge 30of the fan support panel 22, is a lower condensate collection pan 32. Afront section of the lower condensate collection pan extends upwardlyand is spaced from the heat exchanger coil 25.

Mounted to the lower surface of the fan support panel 22 is a fanassembly 34, which includes an electric motor 36 adapted to drive a pairof centrifugal fans 38, which are each enclosed in a two-piece scrollhousing 40. Each of scroll housings 40 defines a rectangular upper airoutlet opening 39, which is in air flow communication with therectangular openings 24 in the fan support panel 22.

As a result of the above-described arrangement of components, when thefan assembly is energized, air is drawn into the region 41 underlyingthe fan support panel 22 through the open front. The air is thendirected upwardly through the rectangular openings 24, through the heatexchanger coil 25 and is discharged through an opening 42 defined by theupper edge 44 of the lower condensate pan 32 and the front edge 46 ofthe upper condensate pan 28.

The heat exchanger 25 is of the cross flow type and includes a left-handtube sheet 48 and a right-hand tube sheet 50, both of which arebasically formed from an elongated U-shaped channel. The left-hand tubesheet comprises a planar center section 52 interconnected to a backflange 54 and front flange 56, both extending substantiallyperpendicular to the planar center section 52 and to the right, asviewed in the drawing figures.

The right-hand tube sheet, likewise, comprises a planar center section58 and a back flange 60 and a front flange 62, extending to the right ina similar orientation to those on the left-hand tube sheet. The backflanges 54 and 60 of each of the tube sheets are each provided withthree rectangular openings all generally bearing the reference numeral64. The opening 64 will be referred to at different times as the upper,center and lower openings of the respective tube sheet and back flangein which they are found.

The heat exchanger further includes a plurality of refrigerant tubes 66extending between the tube sheets 48 and 50. The tubes 66 areinterconnected by a plurality of hairpin turns 68, as is conventional,to define the refrigerant circuit through the heat exchanger. Aplurality of vertically extending heat exchange fins 70 are carried bythe tubes and are oriented substantially parallel to the planar centersections 52 and 58 of the tube sheets.

As best seen in FIG. 2, the previously described inclined surfaces 26 ofthe structural internal side covers 20 are positioned and configuredsuch that they are spaced to receive the back flanges 54 and 60 of thetube sheets 48 and 50 in confronting supporting relationship therewith.Further, as best seen in FIG. 2, for the right-hand side cover and FIG.8 for the left-and side cover, each of the inclined surfaces 26 isprovided with an upper, center and lower 72, 73 and 74, respectively,upstanding structural protrusions. Each of these protrusions has anenlarged rectangularly shaped head section 75 configured to pass throughthe upper and lower rectangular openings 64 on the back flanges 54 and60 of the tube sheets. Each of the protrusions 72, 73 and 74 isconnected to its respective inclined surface 26 by a narrow root portion76 to thereby define a narrow slot 78 between the lower surface of theenlarged head 75 and the inclined surface 26.

It will be noted that the center protrusions 73 are further providedwith an integrally formed structural extension 80 on the upper sidethereof. The upward extensions 80 are provided with an opening 82therethrough, which extends substantially perpendicular to the planarcenter sections 52 and 58 of the tube sheets.

Installation of the heat exchanger 25 to the indoor unit 10 isaccomplished by orienting the heat exchanger in confronting relationwith the inclined surfaces 26, as illustrated in FIG. 2. The heatexchanger is manipulated such that the back flanges 54 and 60 of thetube sheets are in confronting relation with the inclined surfaces 26,with the upper, center and lower protrusions 72, 73 and 74 extendingthrough the respective mating rectangular openings 54 provided in theback flanges 54 and 60. Following such alignment (which is illustratedschematically in FIG. 5, for the right-and tube sheet 50 and a centerprotrusion 73) the entire heat exchanger is manually displaced to theright as represented by the arrows in FIGS. 2, 3 and 6 to thereby resultin a portion of the back flanges 54 and 60 adjacent the rectangularopening 64 to slide into the slots 78 defined by each of the uppercenter and lower protrusions. Such engagement is shown in detail in FIG.6. Following such engagement, each of the tube sheets 48 and 50 isretained under the head section 75 of each of the upper center and lowerprotrusions.

As best shown in FIGS. 5 and 6, in order to assure retention of the heatexchanger in the above-described structural support relationship, asingle self-tapping threaded fastener 84 is passed through the axialopening 82 in the structural extension of the center protrusion 73adjacent to the planar center section 58 of the right-hand tube sheet.An appropriately sized opening 86 is provided in the center section ofthe tube sheet in axial alignment with the opening 82 such that theself-tapping screw 84 may be positively threaded into the hole in thetube sheet to thereby draw the tube sheet 50 and the entire heatexchanger 25 to the right and into a permanent positive structuralsupport relationship, as described above.

As an optional additional attachment of the heat exchanger, asillustrated in FIG. 7, a second additional attachment screw 88 may bepassed through a clearance opening 90 in the planar center section 52 ofthe left-hand tube sheet and threaded into an opening 94 in thestructural extension of the center protrusion on the left-hand inclinedsurface, which opening is sized to be threadably engaged by theadditional fastening screw 88.

What is claimed is:
 1. A heat exchanger and support structure for theheat exchanger, said heat exchanger comprising: a first tube sheethaving a first substantially planar mounting flange, said flange havingat least one opening formed therein, said opening defining an edgefacing in a predetermined direction; a second tube sheet having a secondsubstantially planar mounting flange, said flange having at least oneopening formed therein, said opening defining an edge facing in apredetermined direction, said second tube sheet being spaced from saidfirst tube sheet, and said first and second planar mounting flangesbeing in substantially the same plane; said support structurecomprising: a first substantially planar support surface adapted toreceive said planar mounting flange of said first tube sheet in parallelconfronting relationship therewith, said support surface havingintegrally formed therein an upstanding structural protrusion having aroot section and an upper enlarged section, said enlarged section beingconfigured to pass through said opening in said first flange, said rootsection and said enlarged section defining, together with said planarsupport surface, a narrow slot configured to receive said edge of saidfirst tube sheet's mounting flange therein; a second substantiallyplanar support surface adapted to receive said planar mounting flange ofsaid second tube sheet in parallel confronting relationship therewith,said support surface having integrally formed therewith an upstandingstructural protrusion having a root section and an upper enlargedsection, said enlarged section being configured to pass through saidopening in said second flange, said root section and said enlargedsection defining, together with said planar support surface, a narrowslot configured to receive said edge of said second tube sheet'smounting flange therein; said first tube sheet having a structuralportion extending substantially perpendicularly from said mountingflange, said perpendicular structural portion being spaced from saidedge and having an opening formed therein; said upper enlarged sectionof said structural protrusion of said first support surface having aportion thereof in spaced relation with said perpendicular section ofsaid first tube sheet, said portion having an opening therein in axialalignment with said opening in said perpendicular section; a threadedfastener configured to pass through said opening in said portion andinto threaded engagement with said opening in said perpendicularsection; whereby when said first and second tube sheets are positionedwith said edge in confronting relation with said mating slots, and saidthreaded fastener is actuated to engage said perpendicular section, saidedges are drawn into engagement with said slots to thereby attach saidheat exchanger to said first and second support surfaces.
 2. Theapparatus of claim 1 wherein each of said first flange and said secondflange have a plurality of openings formed therein and, wherein each ofsaid first support surface and said second support surface haveupstanding structural protrusions formed thereon at locations tocooperate with each of said openings in their respective mating flanges.3. The apparatus of claim 2 wherein only one of said upstandingstructural protrusions has said portion thereof in spaced relation withsaid perpendicular section of said first tube with said opening therein.4. The apparatus of claim 2 wherein one of said upstanding structuralprotrusions of said first planar support surface and one of saidupstanding structural protrusions of said second planar support surfacehave said portions thereof in spaced relation with said perpendicularsection of said first and second tube sheets, respectively, with saidopenings therein.